At first glance, the 9th-century Holy Cross Church is reminiscent of any pueblo church in America's Southwest. The church's whitewashed exterior is all shadow and angle in the direct Mediterranean sun, thanks to the cathedral's shape in the form of a cross. Holy Cross bills itself as the world's smallest cathedral, and it is a mysterious showstopper. According to Mladen Pejakovic, a Dubrovnik artist, besides being a place of worship, Holy Cross is also a giant sun dial and calendar. Pejakovic posits that the church is situated and constructed according to exact mathematical calculations that allow the sun's rays to fall on the floor and walls in such a way that they can be used to tell time and graph the summer and winter solstices.